衡水老白干酒中产酸微生物的分离鉴定及性能研究

有机酸是白酒的重要呈味物质，也是香味成分的前驱物质。利用气相色谱和高效液相色谱检测出衡水老白干酒中含有乙酸、丙酸、异丁酸、丁酸、异戊酸和乳酸等6种有机酸。经试验在大曲、酒醅中分离得到69株产酸菌，其中具有代表性的醋酸菌1株，乳酸菌4株，丙酸菌2株。对其中一株主要产酸菌进行了16S rDNA鉴定为食窦魏斯氏菌（Weissella cibaria），并对其的产酸特性进行初步研究，结果表明，在初始pH值6.5，接种量7%，温度32 ℃，培养36 h时乳酸产量最高，为7.12 mg/mL。

Separation,identification and performances of acid-producing microorganism from Hengshui Laobaigan Baijiu

Organic acids are important flavor components in Baijiu (Chinese liquor), and also the precursor of aroma components. Six kinds of organic acids (acetic acid, propionic acid, isobutyric acid, butyric acid, isovaleric acid and lactic acid) were determined by GC and HPLC. 69 acid-production bacteria strains were separated and obtained from Daqu and fermented grains, in which the representative bacteria were 1 strain of acetic bacteria, 4 strains of lactic acid bacteria and 2 strains of propionic acid bacteria. The main acid-producing bacteria were identified as Weissella cibaria by 16S rDNA, and its acid-production performance was researched preliminarily. The results showed that in the conditions of the initial pH 6.5, inoculum 7%, temperature 32 ℃ and time 36 h, the lactic acid yield could reach up to the highest of 7.12 mg/ml.